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1.
Artículo en Inglés | MEDLINE | ID: mdl-32630030

RESUMEN

Wild ginseng, Panax ginseng Meyer, is a traditional medicine widely used in Asia. Due to low reward and high costs, wild ginseng is produced by a plant cell culture technique called cultured ginseng roots (GR). The health benefits of wild ginseng have been well studied, but the potential health effects of GR are largely unknown. Thus, we investigated the role of a GR extract (GRE) on inflammatory responses. We firstly investigated the anti-inflammatory potential of GRE in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. GRE (100 µg/mL) dampened pro-inflammatory gene expression, cytokine release, reactive oxygen species (ROS) production, and mitogen-activated protein kinase (MAPK) activation. These anti-inflammatory responses by GRE were confirmed in mouse bone marrow-derived macrophages (BMDMs), which showed that GRE could inhibit inflammation with the induction of antioxidant levels. LPS was recently reported to impair mitochondrial bioenergetics in mouse macrophages. We next measured the mitochondrial oxygen consumption rate (OCR), determining mitochondrial function. LPS treatment downregulated OCR; however, GRE partially restored the LPS-mediated energy homeostasis defects. Furthermore, GRE-pretreated conditioned media (CM) obtained from mouse macrophages decreased CM-mediated adipocyte inflammation. Collectively, these data suggested that GRE attenuated LPS-induced inflammation, and it might be partially involved in the protection from mitochondrial dysfunction in macrophages and adipocytes.


Asunto(s)
Lipopolisacáridos , Panax , Extractos Vegetales , Adipocitos/efectos de los fármacos , Animales , Antiinflamatorios/farmacología , Asia , Citocinas , Lipopolisacáridos/toxicidad , Macrófagos/efectos de los fármacos , Ratones , Extractos Vegetales/farmacología
2.
Nutrients ; 11(5)2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31052468

RESUMEN

In the normal physiological state, intestinal epithelial cells act as a defensive frontline of host mucosal immunity to tolerate constant exposure to external stimuli. In this study, we investigated the potential anti-inflammatory and gut permeability protective effects of Laminaria japonica (LJ) water extract (LJE) and three types of fermented Laminaria japonica water extracts (LJE-F1, LJE-F2, and LJE-F3) in lipopolysaccharide (LPS)-stimulated Caco-2, human intestinal epithelial cells. All four extracts significantly decreased the production of nitric oxide and interleukin-6 induced by LPS stimulus. In addition, LJE and the three types of LJE-Fs also inhibited LPS-induced loss of monolayer permeability, as assessed by changes in transepithelial electrical resistance. All four LJ extracts significantly prevented the inhibition of the protein levels of occludin, whereas LJE, LJE-F1, and LJE-F3 significantly attenuated the reduction in phosphorylation of adenosine monophosphate-activated protein kinase compared with the LPS-treated group in Caco-2 cells. In conclusion, LJE and its fermented water extracts appear to have potential gut health-promoting effects by reducing inflammation and partially regulating the tight junction-related proteins in human intestinal epithelial cells. Thus, additional studies are warranted to evaluate Laminaria japonica as a therapeutic agent for inflammatory bowel diseases.


Asunto(s)
Antiinflamatorios/farmacología , Células Epiteliales/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Laminaria/química , Extractos Vegetales/farmacología , Células CACO-2 , Humanos , Inflamación/metabolismo , Lipopolisacáridos , Permeabilidad , Proteínas de Uniones Estrechas/metabolismo
3.
Int J Mol Sci ; 20(5)2019 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-30862029

RESUMEN

Peanut sprouts (PS), which are germinated peanut seeds, have recently been reported to have anti-oxidant, anti-inflammatory, and anti-obesity effects. However, the underlying mechanisms by which PS modulates lipid metabolism are largely unknown. To address this question, serial doses of PS extract (PSE) were added to 3T3-L1 cells during adipocyte differentiation. PSE (25 µg/mL) significantly attenuated adipogenesis by inhibiting lipid accumulation in addition to reducing the level of adipogenic protein and gene expression with the activation of AMP-activated protein kinase (AMPK). Other adipocyte cell models such as mouse embryonic fibroblasts C3H10T1/2 and primary adipocytes also confirmed the anti-adipogenic properties of PSE. Next, we investigated whether PSE attenuated lipid accumulation in mature adipocytes. We found that PSE significantly suppressed lipogenic gene expression, while fatty acid (FA) oxidation genes were upregulated. Augmentation of FA oxidation by PSE in mature 3T3-L1 adipocytes was confirmed via a radiolabeled-FA oxidation rate experiment by measuring the conversion of [³H]-oleic acid (OA) to [³H]-H2O. Furthermore, PSE enhanced the mitochondrial oxygen consumption rate (OCR), especially maximal respiration, and beige adipocyte formation in adipocytes. In summary, PSE was effective in reducing lipid accumulation in 3T3-L1 adipocytes through mitochondrial fatty acid oxidation involved in AMPK and mitochondrial activation.


Asunto(s)
Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Arachis/química , Ácidos Grasos/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Oxidación-Reducción , Extractos Vegetales/farmacología , Triglicéridos/metabolismo , Células 3T3-L1 , Proteínas Quinasas Activadas por AMP/metabolismo , Adipogénesis/efectos de los fármacos , Animales , Respiración de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Flavonoides/química , Metabolismo de los Lípidos/efectos de los fármacos , Ratones , Consumo de Oxígeno , Fitoquímicos/química , Fitoquímicos/farmacología , Extractos Vegetales/química , Polifenoles/química , Resveratrol/química
4.
Nutrients ; 10(4)2018 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-29659527

RESUMEN

Laminaria japonica (LJ) and Hizikia fusiforme (HF) are brown seaweeds known to have various health-promoting effects. In this study, we investigated the anti-diabetic effects and possible mechanism(s) of LJ and HF by using both in vitro and in vivo models. C2C12 myotubes, mouse-derived skeletal muscle cells, treated with LF or HF extracts were used for the in vitro model, and muscle tissues from C57BL/6N mice fed a high-fat diet supplemented with 5% LF or HF for 16 weeks were used for the in vivo model. Although both the LF and HF extracts significantly inhibited α-glucosidase activity in a dose-dependent manner, the HF extract had a superior α-glucosidase inhibition than the LF extract. In addition, glucose uptake was significantly increased by LJ- and HF-treated groups when compared to the control group. Phosphorylation of protein kinase B and AMP-activated protein kinase was induced by LJ and HF in both the vivo and in vitro skeletal muscle models. Furthermore, LJ and HF significantly decreased tumor necrosis factor-α whereas both extracts increased interleukin (IL)-6 and IL-10 production in lipopolysaccharide-stimulated C2C12 myotubes. Taken together, these findings imply that the brown seaweeds LJ and HF could be useful therapeutic agents to attenuate muscle insulin resistance due to diet-induced obesity and its associated inflammation.


Asunto(s)
Inflamación/tratamiento farmacológico , Músculo Esquelético/efectos de los fármacos , Phaeophyceae/química , Extractos Vegetales/farmacología , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Citocinas/genética , Citocinas/metabolismo , Diabetes Mellitus , Dieta Alta en Grasa , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Inhibidores de Glicósido Hidrolasas , Inflamación/inducido químicamente , Laminaria/química , Masculino , Ratones , Ratones Endogámicos C57BL , Extractos Vegetales/química , alfa-Glucosidasas/metabolismo
5.
J Med Food ; 20(6): 610-617, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28622115

RESUMEN

Kochujang, a Korean fermented soybean-based red pepper paste, has been reported to have beneficial health effects. The aim of this study was to examine the antiobesity effects of Kochujang as a supplement in overweight/obese subjects according polymorphisms in the obesity-linked gene, peroxisome proliferator activator receptor γ (PPARγ2). Sixty overweight/obese subjects, who had body mass indexes (BMI, kg/m2) ≥23 or waist/hip ratios (WHR) ≥0.90 for males or ≥0.85 for females, were randomly assigned to either taking 32 g/day of placebo or Kochujang for 12 weeks. Before and after the intervention, anthropometric and metabolic parameters and body fat distribution (by computed tomography) were measured. After PPARγ2 C1431T polymorphism was analyzed by PCR-restriction fragment length polymorphism, the differences among the four groups (wild and mutant alleles in Kochujang and placebo groups) were determined. Between the Kochujang (n = 26) and placebo (n = 27) groups, there were no differences in body composition, insulin resistance, or antioxidant biomarkers before and after intervention. Compared to placebo, Kochujang significantly decreased plasma triglyceride (TG), TG/high-density lipoprotein (HDL), and dietary intakes of protein, sodium, and potassium after age, sex, and BMI were adjusted. The beneficial effects of Kochujang on lowering of TG and TG/HDL were weakened in subjects with the PPARγ2 mutant T allele with increasing subcutaneous fat area. However, the interaction between Kochujang and the PPARγ2 T allele improved insulin sensitivity. The obesogenic variables affected by the T mutant allele of PPARγ2 C1431T SNP were different in overweight/obese subjects in response to Kochujang.


Asunto(s)
Fármacos Antiobesidad/metabolismo , Capsicum/metabolismo , Glycine max/metabolismo , Obesidad/dietoterapia , Obesidad/genética , Sobrepeso/dietoterapia , Sobrepeso/genética , PPAR gamma/genética , Adulto , Alelos , Método Doble Ciego , Femenino , Fermentación , Humanos , Lipoproteínas HDL/metabolismo , Masculino , Persona de Mediana Edad , Obesidad/metabolismo , Sobrepeso/metabolismo , Polimorfismo de Nucleótido Simple , Alimentos de Soja/análisis , Triglicéridos/metabolismo , Adulto Joven
6.
Artículo en Inglés | MEDLINE | ID: mdl-27843479

RESUMEN

The extract of Psoralea corylifolia seeds (PCE) has been widely used as a herbal medicine because of its beneficial effect on human health. In this study, we investigated the protective effects and molecular mechanisms of PCE on palmitate- (PA-) induced toxicity in PC12 cells, a neuron-like cell line. PCE significantly increased cell viability in PA-treated PC12 cells and showed antiapoptotic effects, as evidenced by decreased expression of cleaved caspase-3, cleaved poly(ADP-ribose) polymerase, and bax protein as well as increased expression of bcl-2 protein. In addition, PCE treatment reduced PA-induced reactive oxygen species production and upregulated mRNA levels of antioxidant genes such as nuclear factor (erythroid-derived 2)-like 2 and heme oxygenase 1. Moreover, PCE treatment recovered the expression of autophagy marker genes such as beclin-1 and p62, which was decreased by PA treatment. Treatment with isopsoralen, one of the major components of PCE extract, also recovered the expression of autophagy marker genes and reduced PA-induced apoptosis. In conclusion, PCE exerts protective effects against lipotoxicity via its antioxidant function, and this effect is mediated by activation of autophagy. PCE might be a potential pharmacological agent to protect against neuronal cell injury caused by oxidative stress or lipotoxicity.

7.
Oncol Rep ; 35(3): 1566-72, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26707164

RESUMEN

Selenium has received much attention as an anticancer agent, although the mechanisms of action underlying its pro-apoptotic properties remain unclear. Tumors that respond well to antioxidant treatments, such as hepatocellular carcinoma (HCC), may benefit from treatment with selenium as this compound also has antioxidant properties. Furthermore, a major oncogenic driver in HCC is the nuclear transcription co-activator, ß-catenin. In the present study, we examined the mechanism by which selenium reduces survival of HCC cells, and whether this was associated with modulation of the ß-catenin pathway. Hep3B cell lines and cancer cell xenografted animals were treated with selenium, and apoptotic events or signals such as AMPK, ß-catenin and GSK3ß were determined. Further interactions among ß-catenin, glycogen synthase kinase 3ß (GSK3ß), and AMPK were explored by applying AMPK small interfering RNA (siRNA) or GSK3ß siRNA with western blotting or immunofluorescence microscopic observation. Selenium activated AMPK, which in turn suppressed ß-catenin. Selenium induced the translocation of AMPK into the nucleus and prevented the accumulation of ß-catenin therein. Upon inactivation of AMPK by AMPK siRNA, selenium no longer modulated ß-catenin, implying that AMPK is an upstream signal for ß-catenin. We found that the binding between AMPK and ß-catenin occurs in the cytosolic fraction, and therefore concluded that the cancer cell antiproliferative effects of selenium are mediated by a GSK3ß-independent AMPK/ß-catenin pathway, although AMPK-mediated GSK3ß regulation was also observed. We primarily discovered that AMPK is a crucial regulator initiating selenium-induced inhibition of ß-catenin expression. Taken together, these novel findings help to illuminate the molecular mechanisms underlying the anticancer effect of selenium and highlight the regulation of ß-catenin by selenium.


Asunto(s)
Proteínas Quinasas Activadas por AMP/biosíntesis , Carcinoma Hepatocelular/tratamiento farmacológico , Glucógeno Sintasa Quinasa 3/biosíntesis , Neoplasias Hepáticas/tratamiento farmacológico , Selenio/administración & dosificación , beta Catenina/biosíntesis , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Citosol , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3 beta , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Ratones , Unión Proteica , ARN Interferente Pequeño , Ensayos Antitumor por Modelo de Xenoinjerto , beta Catenina/genética , beta Catenina/metabolismo
8.
BMC Complement Altern Med ; 14: 109, 2014 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-24666969

RESUMEN

BACKGROUND: Activation of the Wnt pathway is known to promote tumorigenesis and tumor metastasis, and targeting Wnt pathway inhibition has emerged as an attractive approach for controlling tumor invasion and metastasis. The major pathway for inhibiting Wnt is through the degradation of ß-catenin by the GSK3-beta/CK1/Axin/APC complex. It was found that Hep3B hepato-carcinoma cells respond to anthocyanins through GSK3-beta-induced suppression of beta-catenin; however, they cannot dephosphorylate GSK3-beta without AMPK activation. METHODS: We tested the effects of anthocyanins on proliferation and apoptosis by MTT and Annexin V-PI staining in vitro. Mouse xenograft models of hepato-carcinomas were established by inoculation with Hep3B cells, and mice were injected with 50 mg/kg/ml of anthocyanins. In addition, protein levels of p-GSK3-beta, beta-catenin, p-AMPK, MMP-9, VEGF, and Ang-1 were also analyzed using western blot. RESULTS: Anthocyanins decrease phospho-GSK3-beta and beta-catenin expression in an in vivo tumor xenograft model, increase AMPK activity in this model, and inhibit cell migration and invasion, possibly by inhibiting MMP-2 (in vitro) and the panendothelial marker, CD31 (in vivo). To elucidate the role of the GSK3-beta/beta-catenin pathway in cancer control, we conditionally inactivated this pathway, using activated AMPK for inhibition. Further, we showed that AMPK siRNA treatment abrogated the ability of anthocyanins to control cell proliferation and metastatic potential, and Compound C, an AMPK inhibitor, could not restore GSK3-beta regulation, as exhibited by anthocyanins in Hep3B cells. CONCLUSION: These observations imply that the AMPK-mediated GSK3-beta/beta-catenin circuit plays crucial roles in inhibiting cancer cell proliferation and metastasis in anthocyanin-treated hepato-carcinoma cells of Meoru origin.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Antocianinas/farmacología , Glucógeno Sintasa Quinasa 3/metabolismo , Neoplasias/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/farmacología , Vitis/química , Animales , Antocianinas/uso terapéutico , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/uso terapéutico , Proliferación Celular , Modelos Animales de Enfermedad , Frutas/química , Glucógeno Sintasa Quinasa 3 beta , Humanos , Masculino , Ratones Endogámicos BALB C , Invasividad Neoplásica , Neoplasias/metabolismo , Neoplasias/patología , Extractos Vegetales/uso terapéutico , República de Corea , Trasplante Heterólogo , Vía de Señalización Wnt , beta Catenina/metabolismo
9.
Eur J Pharmacol ; 643(2-3): 225-31, 2010 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-20599908

RESUMEN

Pentylenetetrazol (PTZ) has been shown to induce seizure-like behavior, learning deficits in passive avoidance response test, and an increase in hsp70 (heat shock protein 70) mRNA expression in the adult zebrafish; PTZ has been increasingly appreciated as an excellent model system for the study of seizures. In this study, we demonstrate that valproic acid (VPA), an antiepileptic drug, suppresses seizure-like behavior and improves learning ability in adult zebrafish treated with PTZ. Pretreatment with VPA significantly reduces rapid involuntary movement and abrupt changes in moving direction in the PTZ-treated zebrafish. PTZ-induced learning impairments were also improved in the zebrafish pretreated with 200 or 500 microM VPA. However, the scopolamine-induced impairments of learning ability were not improved by VPA pretreatment. It is worth noting that while the zebrafish treated with 500 microM VPA for 1-3 weeks learned the passive avoidance response, those treated with 1 or 2mM VPA for 3h didn't. Furthermore, the increased level of hsp70 expression induced by PTZ, a stress marker protein, was significantly reduced in the VPA-pretreated zebrafish brains. Collectively, our data show the antiepileptic effects of VPA in the adult zebrafish, which coincides with reduced hsp70 mRNA expression, rescued learning impairment under PTZ-treated conditions.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Discapacidades para el Aprendizaje/prevención & control , Fármacos Neuroprotectores/uso terapéutico , Pentilenotetrazol/toxicidad , Ácido Valproico/uso terapéutico , Animales , Anticonvulsivantes/administración & dosificación , Reacción de Prevención/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Encéfalo/metabolismo , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Discinesia Inducida por Medicamentos/prevención & control , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Discapacidades para el Aprendizaje/inducido químicamente , Locomoción/efectos de los fármacos , Antagonistas Muscarínicos/toxicidad , Fármacos Neuroprotectores/administración & dosificación , ARN Mensajero/metabolismo , Escopolamina/toxicidad , Convulsiones/inducido químicamente , Convulsiones/prevención & control , Factores de Tiempo , Ácido Valproico/administración & dosificación , Pez Cebra
10.
Carcinogenesis ; 31(6): 1092-9, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20164123

RESUMEN

Activation of the mammalian target of rapamycin (mTOR) pathway promotes tumorigenesis, and inhibiting the mammalian target of rapamycin complex 1 (mTORC1) has emerged as an attractive target for suppressing tumor growth. We found that selenium treatment of HT-29 colon cancer cells suppressed mTORC1 through Akt-independent and -dependent pathways. In Akt-independent mTORC1 inhibition in selenium-treated colon cancer cells, adenosine monophosphate-activated protein kinase (AMPK) alpha(1) was crucial for suppression of mTORC1 activity. In contrast, the Akt-dependent mTORC1 inhibition by selenium did not require AMPKalpha(1). The importance of the AMPKalpha(1)-mTORC1 pathway in mediating the antiproliferative action of selenium was examined in xenograft tumors, and the suppression of mTORC1 as well as Akt was concomitant with an increase in AMPKalpha(1) activity. These findings suggest that the antiproliferative effect of selenium is mediated by an Akt-independent AMPKalpha(1)/mTORC1 pathway or by the Akt/tuberous sclerosis complex 2 /mTORC1 pathway.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Neoplasias del Colon/metabolismo , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Selenio/farmacología , Animales , Western Blotting , Proliferación Celular , Neoplasias del Colon/enzimología , Neoplasias del Colon/patología , Activación Enzimática , Células HT29 , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Fosforilación , ARN Interferente Pequeño , Serina-Treonina Quinasas TOR
11.
Ann N Y Acad Sci ; 1171: 484-8, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19723093

RESUMEN

In this study, we investigated the molecular basis of Korean kidney bean husk extract, with emphasis on its ability to control intracellular signaling cascades of AMP-activated protein kinase (AMPK) responsible for inducing antitumor activities in colon cancer cells. Recently, the evolutionarily conserved serine/threonine kinase, AMPK, has emerged as a possible target molecule of tumor control. We investigated the effects of Korean kidney bean husk extract on apoptosis regulation and the activation of AMPK. Korean kidney bean husk extract exhibited a series of antitumor effects such as cell death and apoptotic body appearance. These antitumor potentials were accompanied by the increase in p-AMPK and p-Acc as well as antitumor proteins p53 and p21. The stimulation of AMPK by this extract was blocked with the synthetic AMPK inhibitor Compound C at 10 micromol/L, and the combined treatment of Compound C and the AMPK activator AICAR (5-aminoimiazole-4-carboxamide-1-beta-D-ribofuranoside) showed that Compound C could inhibit the activation of AMPK at the concentration of 20 micromol/L. In conclusion, the ability of carcinogenesis control by Korean kidney bean husk extract with high potency suggests its value as an antitumor agent in colon cancer therapy.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Phaseolus/química , Extractos Vegetales/farmacología , Proteínas Quinasas Activadas por AMP/antagonistas & inhibidores , Acetil-CoA Carboxilasa/metabolismo , Western Blotting , Caspasa 3/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Células HT29 , Humanos , Pirazoles/farmacología , Pirimidinas/farmacología , Transducción de Señal/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo
12.
Ann N Y Acad Sci ; 1171: 538-44, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19723101

RESUMEN

This study investigated the apoptotic regulation by green tea catechin epigallcatechin-3-gallate (EGCG) on colon cancer cells in the presence of low-dose H(2)O(2) known to exert the activation of signal pathways leading to cell proliferation. In the presence of low-dose H(2)O(2), EGCG induced apoptosis and abolished the cell-proliferative effect exhibited by low-dose H(2)O(2). This reduction of growth was accompanied by an activation of AMP-activated kinase (AMPK), a decrease in cyclooxygenase-2 (COX-2) expression and prostaglandin E(2) (PGE(2)) levels, and the induction of apoptotic markers such as p53 and poly(ADP-ribose) polymerase (PARP) cleavage. The low-dose H(2)O(2) stimulated COX-2 expression, and treating cells with synthetic AMPK activator AICAR (5-aminoimiazole-4-carboxamide-1-beta-d-ribofuranoside) resulted in greater suppression of COX-2 expression and PGE(2). By treating cells with high concentrations of the reactive oxygen species (ROS) scavenger NAC (N-acetyl-1-cysteine), the apoptotic effect of EGCG was abolished and led to suppression of AMPK and COX-2, indicating that the liberation of excessive ROS might be the upstream signal of the AMPK-COX-2 signaling pathway even in the presence of low-dose H(2)O(2).


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Apoptosis/efectos de los fármacos , Catequina/análogos & derivados , Ciclooxigenasa 2/metabolismo , Peróxido de Hidrógeno/farmacología , Transducción de Señal/efectos de los fármacos , Té/química , Acetilcisteína/farmacología , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacología , Western Blotting , Catequina/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Dinoprostona/metabolismo , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Células HT29 , Humanos , Oxidantes/farmacología , Poli(ADP-Ribosa) Polimerasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ribonucleótidos/farmacología , Proteína p53 Supresora de Tumor/metabolismo
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